3144 - Minimum Substring Partition of Equal Character Frequency.

Medium

Given a string s, you need to partition it into one or more balanced substrings. For example, if s == "ababcc" then ("abab", "c", "c"), ("ab", "abc", "c"), and ("ababcc") are all valid partitions, but <code>("a", "bab" , "cc")</code>, <code>( "aba" , "bc", "c")</code>, and <code>("ab", "abcc" )</code> are not. The unbalanced substrings are bolded.

Return the minimum number of substrings that you can partition s into.

Note: A balanced string is a string where each character in the string occurs the same number of times.

Example 1:

Input: s = "fabccddg"

Output: 3

Explanation:

We can partition the string s into 3 substrings in one of the following ways: ("fab, "ccdd", "g"), or ("fabc", "cd", "dg").

Example 2:

Input: s = "abababaccddb"

Output: 2

Explanation:

We can partition the string s into 2 substrings like so: ("abab", "abaccddb").

Constraints:

• 1 <= s.length <= 1000

• s consists only of English lowercase letters.